Gripper



kJuly 11, 1933. H C, PORTER 1,917,663

' GRIPPER Filed July 14. 1952 5 Sheets-Sheet l J j] 22 g f j y 1 I \l/ Il fi' a n 135 619 @tra 138 7619 Z5? July 11, 1933- H. c. PORTER 1,917,653

GRIPPER Filed July 14, 1932 5 sheets-sheet 2 my M, F1933. H. c. PORTER GRIPPER Filed July 14, 1932 3 Sheets-Sheet 3 J5, j] l Zig a ,f

Patented `luly 1K1, 1933` y unirse-f gSTATES PAT-Entornos nov/*Ann c. ron-TER, or LA GnnNe-nrAnx, ILL1NoIs,`assrGnon rro sreivonn srnarrrnecorrreuy, or CHICAGO, ILLINOIS, A conroearroiq or DELAWARE enrrrnn applicati@ filed July 14,

My invention relates to ygrippers. i

More particularly it relates vto and will be illustrated and described as embodied in a gripper especially V:adapted for use in grip ping and holding abinder for packages and the like, such as steel strap or Wire. Such grippers are particularly useful inV hinder tensioning or stretching tools and.' machines employedv in V,the strapping or binding of packages. `or groups of packages. Examples of such tools are illustrated in Sidney W. Treat Patent No.V 1,762,535 granted IJ une 10, 1930 and .the copending application of Emil G. Seagren, ASerial No. 614,429 .tiled 3l, 1932. Y One of the objects of my invention is to -provide an i Vprovedgripper.

further object iste provide a gripper which will be equally effective when used with binders ofV different thickness.

Anotherk object is to provide a gripper Whichwill not obj-cctionahly mar or weaken the binder material held fbyfit, i

Another *object is to provide a gripper Which Willso distribute its actionover a considerable area l'of binder that inthe event grip increasing teeth are employed they need not unduly bite Vvinto the binder to insure Ka firm hold thereupon. s j

Another object is to provide a gripper which will take a irmhold upon the binder although requiring little manual effort to insure proper action. Y

Another object is :to yprovide an limproved gripper which Will automaticallyincrease its gripping actionin accordance with the increase ot tensionl or pull upon the binder held thereby. Y Y f v ,F

Another object is ,to providea gripper which L.may be easily disengaged from the binder even thoughthebinderyis under tension. l

yAnother object is` to provide a gripper Which will not' damage the binder when disengaged therefrom, eventhough the hinder is 'under tension.

Other objects and advantages ivill hereinyafter appear. -v

`Enibodiinents ofthe invention are illus- 1932. y serial No. 622,439.

trated in the accompanying dravvingswhere ly as the tension or pull of the binder ini creases.

Fig. 6 is arviewg'similar modified construction.

F ig. 7 'is Ya vertical section of gripper shown in Fig; 6.

Fig. 8 is a section .on the' line 8-8 of Fig.7. 'W Y --l Figs.V 9, l0 and 1l aresimilar views of another modified construction. f

Referring first to Figs. l to 5, the frame 5 'to Figli, of a the modified oi the tensioning tool is Vshown provided with a forwardly -extending foot (ifV This foot 6 forms the stationary member over which the binder 7 passes and against which `the binder is clamped in the gripping operation. The complementarymovable member of the gripper comprises a Wedge shaped gripper block 3 is a section on the line 3-43 of t S which to increase its holding power is pref erably provided Withlteeth 9 orbiting into and securing a iirmer hold upon the binder. The Vtoothed or active face, of the gripper block is flat andalways lies parallel to the binder surface it engages. The opposite side of Jthe gripper block is inclined'downwardly in the direct-ion'of the binder tension, ile., in the direction of `the arroIvs,'to give its Wedge shape and action. The sloping-upper edges of thefgripper loloclr project laterally toform a. pair of keyslO. V

` Y JThe gripper block is carriedby a movable mounting block 1l Which is provided With a longitudinal tapered slot for receiving the gripper block. The upper part of Vthis slot is ormedlinto a pair of keyways which' slidingly receive keys 10, as -most clearly illus# trated in Fig. 3, whereby the gripper block is retained by and movable vertically with the mounting block and also is capable of movement independently of its mountingl block. The sloping wall -orming the top of the tapering slot in the mounting block has a socket 15, which may be of cylindrical shape7 formed therein in communication with the slot. Socket 15 aligns with a cylindrical bore 16 in the inclined inner face of the gripper block and forms therewith a chamber for a helical spring 17. A threaded plug 18 screws into the threaded end of bore 16 so that when the mounting and gripper blocks and spring are assembledthe spring, which abuts the rear wall 19 of soclret 15 at one end and the plug 18 in the bore of th-e gripper block at the other end,'biases the relatively movable gripper block toward the left, as viewed in Figs. 1, 2, 4 and 5. The spring also holds the gripper block-gripper mounting -assembly together because it will not permit the socket and bore 16 to get far enough out or" alignment to permit separation.

The gripper mounting block is loosely mounted upon an eccentric portion 2O of a shaft 21 which shaft is rotatably carried by the tool frame in any desired manner. An operating handle 22 is rigidly attached to a concentric extremity 23 of shaft 21. This attachment may be provided by making the shaft end 23 square and providing handle' 22 with a square socket tol it,-a screw 24 serving to hold the two together. Thus by providing themounting bloclr with a slightly elongated hole 23 to lit upon the cylindrical but eccentric portion-2O ot shaft 21,*the oscillation of the shaft will elevate and lower tl e gripper block. As clearly illustrated in the drawings, rotation of handle 22 in a counterclockwise direction (i. e., elevating its outer end) rotates shaft 21 so as to lower the mounting block to bring the gripper block into engagement with the upper surface of the binder. Movement of the gripper handle in the reverse direction (i. e.,vto the4 position shown in Fig. 1) elevates the mounting bloclt so as to raise the gripper' block from the binder and open the `ripper for the reception of a binder between the gripper block and the foot of the tool. Y Y y `Guide lug25 projecting from'the frame. of the tool engages the rear or right hand side of the mounting block to prevent the same from rotating either in its up and down movements or when subjected to the strain of binder tension. A nsimilar guide lug 26 lies in front or to the left of' the mounting block but spaced therefrom by a narrow clearance gap 27. However, the biasing spring 17 tends to retain the movable gripper block'in contact with this guide lug 26 and also to retain the mounting loclrfagainst guide lug 25. A projection 28 carried by the gripper control handle 22 engages guide lug 25 to limit the downward movement of the handle.

In operation the gripper control handle 22 of the tool is moved downwardly until its stop projection 28 engages lug 25, as shown in Fig. 1, to open the gripper for the reception of the binder. The binder is placed between the gripper bloclr and the foot of the tool and then the controlling handle is moved upwardly or counter-clockwise until the gripper block firmly engages the upper surface of the binder, as shown by the dotted lines of Fig. 2. In this condition the movable gripper block is, under the influence of its biasing spring, held against guide block 26, as shown in Figs. 2 and 4. Now as the tension upon the binder increases in the direction of the arrows (i. e., toward the left as viewed in all figures) the movable gripper block is by that tension caused to move toward the right. And because the mounting block is held rigid the wedge action causes the gripper block to move downwardly into tighter and tighter engagement with the binder as the binder tension pulls the gripper block toward the right. This wedging action causes the gripper block to embed its teeth more firmly into the binder and increase the grip thereupon. It thus insures that the binder will be lirmly held'even though the initial grip is slight and consequently very little effort needs to be exerted on the control handle in'order to insure proper action.

Because of the fact that the gripping surface of the gripper block remains parallel to the plane of the binder and is provided with a relatively extensive gripping face, it is unnecessary that the teeth indent the binder very deeply in order to secure and maintain a iirm hold thereupon and consequently the binder is not unduly marredor weakened.

Tn order to release the binder the controlling handle is again moved to the down position shown in Figl. This release of the binder can be accomplished easily even thoughthe binder is under tension, because the movement of the gripper mounting block being vertical lifts the teeth of the gripper block straight out of the indentations they have made in the upper surface of the binder.

.Release of the gripper vis also assisted by the wedging action of the gripper block. Thus this wedging action is always tending to raise the supporting block; but during the time the gripper is in action this tendency is resisted by the eccentric connection between the mounting block and the shaft and the vfriction of the bearings. But when this resistance or opposition is almost wholly removed with the rotation of the shaft to raise the mounting block the wedging action of the gripper assists in the elevation of the mounting block. Y Consequently the effort required to release the gripper, even when the binder ics elevated out of the indentations inthebincflerthe stretch of the strap cannot cause relative movement betweenthebinder and the 'teethof the gripper block.V Suchmovement, which was characteristic in prior grippers, resulted in the binder surfacebeing cutor scored by the gripper teeth. The elimination of this undesirable relative movement is brought about by the fact that, as the Vbinder moves toward the right whenthe gripis released, the gripper block isV free to Jfollow except for the relatively slight oppositionV afforded vby spring 17. This movement of the gripper block with the binder enables the teeth` to be lifted outof the'indentations inthe binder with'little effort and without danger ofsc'oring the binder. Vhen the mounting block hasbeen elevated suiiiciently completely to withdraw the gripper block teeth from the binder impressions, spring 17 returns the gripper block toits initial position against guide 2G. Y

A variety of other arangements may be employed toV produce 'the' movements of the mounting block perpendicularly to the stationary gripping member whereby" the movable gripper isv moved toward and from the binderf- Y Figs. 6 to 8 show one modication wherein the mounting blockl1!Y is" prinfidedv with a rectangular openingfBO'in which is slidably mounted a rectangular crossfhead 3l. Cross head 31 is journalled upon an eccentric portion 32 of a shaft 21 carried bythe frame. Mounting block 11 carries a wedge shaped gripper block 10', which cooperates with a stationary gripping member 6 to hold a binder 7, and is moved toward and from the stationary member by a handle 22. The operation of this modified construction corresponds essentially with that heretofore described. Y Y

Figs. 9 to 11 show another modified construction for translating slight rotary movements of the control lever shaft into rectilinear movements of the mounting block perpendicularly to the stationary gripping member. This arrangement may be employed when only slight vertical movements of the mounting block are required to bring the movable gripper block into and out of operative position. 'In this construction the mounting block 1l is journalled upon an eccentric portion 35 of the control lever shaft 2l". The

'Y A binder gripper Comprising a frame having a stationary vmember t0 engage' one side of a binder, ai wedgefshaped' movable memberto venga-ge' the" opposite side of the Y binder,- amountingfor'the movable member having a4 slidabley connection therewith, and

from the stationary member.

""2'.' A bindergripper comprisinga-y frame having a stationary member to engage one side of a. binder, a movable'member having ai substantially flat face to' engage the oppositel sideof t-he binder, a mounting for moving the `movable member toward and from the stationary member perpendicular thereto, and an operative connection between the movable member *andv its *mountingvl `whereby movementoffthe binder causes the movable member to approach the stationary member; BfA binder gripper comprising aY frame having a stationary member to engage one side of a binder, a monnting block mountedk on theV frame to move toward and from the stationaryy member Vperpendieular the'rete, the mounting block having a guide disposed at anincline to the stationary member, and a gripper block carried the mounting block and Vhaving a gripping Aface parallel to -side of a binder, la mounting block mountedy 1` on the frame to move toward and from the stationary member perpendicular thereto, said mounting block having a recess therein, a. gripper block located in the recess of the mounting block and having a face to engage the otherlside of the binder, and a key and key'way connection between the mounting meansfor movingz the mounting toward and lio block and gripper block, said keyway being i inclined relative. to the stationary member so that movement of the gripper block parallel'to the stationary member varies the separation therebetween.

5. AV binder gripper comprising a. frame having a stationary member to engage one sideoi a binder, a mounting block mounting l on Vthe frame to move toward and from the stationary member perpendicular thereto, said mounting block having a recess therein, a gripper block located in the recess of the mounting block and having a face to engage the other side of' the binder, a key and theyway connection between the mounting block and gripper block, said keyway being in clined relative to the stationary member so that movement of the gripper block parallel vto the stationary member varies the separa- Vnr tion therebetween, and a spring kbiasing the gripper block in a direction to separate. itr

the opposite side-of the binder, said gripper.

block having a bore .extending therein, a mounting block carried by the frame and movabletoward and from the stationary.,

member perpendicular thereto, said mounting block having a socket therein in alignment with the bore of the gripper block, a key and keyway connection between the gripper block and mounting block, the same being inclinedv relative to the facek of the ystationary membervwhereby movement Aof the gripper blo'ckrelative to the mounting block varies the `separation between the gripper block and the stationary member, a spring located in the aligned bore of the gripper block and socket of' the mounting block to bias the gripper block to move away from the stationary member, and means for moving the mounting block toward andA from the stationary member. I

7. A binder gripper comprising a frame having a stationary member to engage one side of a binder, a gripper block having a substantially flat face to engage the opposite side of the binder, a mounting block carried by the frame to move toward and from the Stationary member, guide means for insuring that the movements of the mounting block are perpendicular to the stationary member, a key and keyway connection between the mounting block and gripper block to permit relative movement therebetween, said connection being inclined to vthe plane of the stationary member so that movement of the gripper block parallel to the stationary member varies the separation, therebetween, and means for-moving the mounting block.

8.,A binder gripper comprising a frame having ay stationary member to engage one side of a binder, a gripper block having a substantially flat face to engage the opposite side of the binder, a mounting block movable toward and from the stationary member perpendicularly thereto, a key and keyway connection' between the gripper and mounting blocks inclinedtoward the stationary member lin the direction of the binder tension, a spring'l for retaining the gripper and mounting blocks together and biasing the gripper block awayA from vthe stationary member, and means for moving the mounting block 'toward and from the stationary member.

9. A'binder gripper Acomprising a frame having a stationary member to engage one side of a binder, a gripper block to engage the opposite side of the binder, a mounting block movable toward and from the stationary member perpendicular thereto, the mounting and gripperblocks having cooperative connections permitting the latter to move parallel to and toward and from the stationary member independently of the mounting block, and means for moving the mounting block.

In witness whereof, I hereunto subscribe my name this 8th day of July, 1932.

y HOVARD C.- PORTER. 

